di·gress / dīˈgres/ • v. [intr.] leave the main subject temporarily in speech or writing: I have digressed a little from my original plan.DERIVATIVES: di·gress·er n.di·gres·sion / -ˈgreshən/ n.di·gres·sive / -ˈgresiv/ adj.di·gres·sive·ly / -ˈgresivlē/ adv.di·gres·sive·ness / -ˈgresivnis/ n.ORIGIN: early 16th cent.: from Latin digress- ‘stepped away,’ from the verb digredi, from di- ‘aside’ + gradi ‘to walk.’

digress XVI. f. dīgress-, pp. stem of L. dīgredī, f. DI- 1 + gradī step, walk, f. gradus step.
So digression XIV. — (O)F. — L.